Cotton processing machines such as cottonseed delinters and cotton gins utilize rotating saws to remove the cotton from the cotton seed. A large number of circular saws are mounted on a common horizontal axis for rotation as an integral unit about the axis. The saws are spaced-apart axially so that there is an axial space between each adjacent pair of saws. A gratefall having a large number of spaced-apart parallel members is positioned during machine operation such that the parallel members extend through respective axial spaces between the saws, there being as many parallel members as there are axial spaces.
For proper operation, it is essential that the entire gratefall be properly positioned relative to the preipheral portions of the circular saws. A gratefall adjusting mechanism is described in U.S. Pat. No. 3,490,101.
A cottonseed delinting machine requires a variable speed feeder to maintain the correct amount of seed in the gratefall--preventing overload or underload conditions.
Existing feeds use ratchet and pawl mechanisms, either in single arrangements such as for standard capacity linters, or in double arrangements for standard capicity linters or for high capacity linters.
In one example a ratchet is mounted on a feed roll shaft and has a shield frame arrangement on one hub and a rocker arm arrangement on the opposite hub. A high capacity model has rocker arms on both hubs.
The shield frame position is governed by a connecting rod attached to a density weight arm located at the end of the gratefall. The arm is connected to a full length curved section in the gratefall which follows a roll of cottonseed. As the seed roll decreases, the weight arm drops, which in turn pulls the shield frame forward, exposing more teeth of the ratchet to engagement by the pawl.
The pawl pivots on one end of the rocker arm which is oscillated by an eccentric and connecting rod arrangement located on a countershaft.
The counter shaft is driven with a flat belt drive from one end of a float shaft. The drive requires an idler as the location of the driving pulley is periodically adjusted to allow for wear in the operating members.
When the cottonseed enters the gratefall from the feeder, the density curve will gradually rise, moving the shield frame to the rear and allowing less of the ratchet to be exposed to the pawl until it is completely disengaged. The ideal arrangement is to have the speed exactly adjusted for a uniform engagement and flow of material. In practice, this is almost impossible to accomplsih with existing feed drives.
Cottonseed processing machinery has an automatic variable speed feeder. Cottonseed flows through a chute into a hopper and out of the hopper onto a gratefall adjacent turning saw blades. A curved section coextensive with the gratefall overlies the gratefall and urages the cottonseed toward the gratefall and saw blades. The sensing means of a switch detects movement of a weighted arm urging the curved section toward the gratefall. A float shaft is rotated between the gratefall and the curved section in the cottonseed roll. Pulleys drive one part of an electric clutch from the clutch shaft. The other part of the electric clutch when energized connected the first part to the speed reducer which in turn drives the feed roll shaft. When the limit switch senses movement of the arm, indicating a movement of the curved section toward the gratefall, a reduced cottonseed roll, and the need for faster feed, the switch energizes the clutch, driving the feed roll from the float roll via the electric clutch and speed reducer. When the curved section returns outward, the switch causes the clutch to disengage.
These and further objects and features of the invention are apparent in the disclosure which includes the above and on-going specification in claims and the drawing.